Door latches



United States Patent filice 3,216,229 Patented Nov. 9, 1965 3,216,229 DR LATCHES Gaylord Moncada, Miami, Fla., assignor to Miller Industries, Inc., Miami, Fla., a corporation of Florida Filed Aug. 2, 1963, Ser. No. 299,670 2 Claims. (Cl. 70-100) This invention relates to door latches and the like, and more particularly the invention relates to door latches for latchng sliding doors.

It is an object of this invention to provide a novel door latch for use in conjunction with sliding doors, for apartment houses, homes, as well as other types of buildings.

It is a further object of this invention to provide a novel door latch device for a sliding door and which may be latched and unlatched from the inside by a manually rotatable knob, and which may be unlatohed from the outside, by a key operated member engaging the rotatable knob and rotating the Same, and which may be prevented from being unlatched from the outside by a slidable knob adapted to engage the rotatable knob and fix it against rnovement.

It is a further object of the invention to provide a night latch which can be easily and simply operated.

Further objects and advantages will become apparent as the description proceeds and when taken in conjunction with the accompanying drawing wherein:

FIGURE 1 is a front view of the night latch as mounted on the panel of a sliding door.

FIGURE 2 is an end view of the door latch with a portion of the door panel breken away.

FIGURE 3 is a longitudinal cross-seetional view of the door latch taken along line 33 of FIGURE 1.

FIGURE 4 is a fragmentary elevational view of the upper portion of the door latch as viewed from the op posite side of FIGURE 1.

FIGURE 5 is a fragmentary cross-sectional view of the door latch taken -along line 5-5 of FIGURE 2.

FIGURE 6 is a cross-sectional fragmentary view taken along line 6-6 of FIGURE 2.

Briefiy stated, the invention comprises a latch assembly for a sliding door comprising a pair of elongated housing assembly members adapted to be introduced in opposed relation on opposte sides of a sliding door, with a rotatable lock plug adapted to receive a key from outside of the door and to rotate with the key, and a manually operated knob mounted to the assembly member to be operated from the inside of the door, a lug on a cam associated with said manually operated knob and rotatable by said knob into and out of engagement with a tongue in a door frame for locking the door to the door frame, said key operated plug having a flange adapted to engage the rotatable knob to rotate the knob out of engagement and a slidable knob mounted beneath the rotatable knob, and adapted to slidably engage the rotatable knob to prevent rotation of the rotatable knob and thereby prevent the knob from being rotated out of engagement by the key-operated plug.

Referring more particularly to the drawings, in FIG- URE 1 the door latch assembly 21 is illustrated as mounted in the sliding door 22 with the latch assembly having an inner housing latch assembly 23 and an outer housing latch assembly 24, as illustrated in FIGURE 2.

The latch assembly housing members 23 and 24 are forrned of cast metal to form a casing for the door latch housing. The latch assembly is adapted to be received in in elongated slot 25 in the sliding door 22. A fixed door frame 22 has a tongue assembly 22" adapted to be engaged by the latch assembly to lock the sliding door to the frame.

A plastic square knob 27 bearing the indicia Nite Lok is mounted to a housing member 23 and has rearwardly extending flange portion 28 slidably received in a slot 29 in the casing member 23, a spring washer 30 mounted in a pair of opposed notched portions 31 and 32 of the flange 28.

The spring washer 30 holds the flange member 28, lug member 28' and knob 27 in positi-on. The tongue engagement member 35 forms an integral part of flange 23 which is gu-ded by guides 33 and 33'.

Mounted above the sliding knob 27 is an operators knob 36. The operators knob 36 is rotatably mounted in a bore 37 of the first front casing 23. The operators knob has an enlarged central body portion 38. Immediately behind the eentral body portion of the operators knob is a metal cam 39. A circular projecting post 40 is formecl integrally with the casing mernber 24 and provides a rotatable hearing support for the cam. The cam 39 is mounted to rotate about the axis of the post and operators knob 36. The cam 39 has square nose 42 fitted in a corres onding square hole 43 in the operators knob, whereby the rotation of the operators knob 36 causes the rotation of the cam 39.

The cam 39 has a laterally offset lug 44 which rotates in an arc about the longitudinal axis of the post 42 and is formed integrally with the central body portion 38 of the cam 39.

On eaeh side of thecentral portion of the cam are fiat elongated spring plates 47 and 48 which engage opposing sides of the central body portion of the cam between lug 44 and then back inner face 49 of the rear casing member 24.

The rear casing 24 has a hollow tubular collar portion 59 forrned integrally with the back casing member 24.

A key plug 51 is rotatably mounted in the tubular collar portion of the back casing. The key plug 51 has a l:ey 52 which is adapted to be slidably received in the key plug and to rotate the key plug about its longitudinal axis. A meta1 plate 53 is mounted to the forward end of the key plug and is adapted to rotate with the key plug. The plate 53 .has a pair of sp-aced fork members 54 and 55 which project downwardly from the centra] portion 53' of the plate 53. The fork members project toward the operators knob.

The front and rear casing members 23 and 24 have recessed channels 56 and 57 which are elongated beneath the sliding knob and are provided to receive the fingers of the operator to facilitate sliding the door 22 open and -closed.

The front -and rear casing members also have a pair of upper and lower screws 58 and 59 which act to secure the casing members together and retain the lock components therebetween in operative relation.

The screws 58 and 59 pass through an upper and lower bore 60 and 61 in the front casing 23 and are threaded into a threaded upper and lower bore portion 62 and 63 in the back casing 24 to secure the casing members together.

The casing members also have flange portions 23 and 24' projecting outwardly on all four sides to overlap the edge of the slot 25 in the door.

The cam member 39 has a rectangular configuration along three sides or faces of its central body portion in the area of the body portion between the flat spring plates 47 and 48. The faces are adapted to engage the spring plates whereby the spring plates are urged against the faces to urge the cam into two positions which are approximately from one -another and retain -it in either of said positions in the absence of force being applied to the operators knob 36 to rotate the same.

The operation of the latch assembly is substantially as follows:

After the latch device has been installed in the door, the sliding door 22 may be slid againts the door frame 22. The operators knob is in the position illustrated in FIGURE 4, whereby the lug 44 is located 90 downward from ts position shown in FIGURES 2 and 6 and within the confines of the key latch assembly.

By rotating the knob 36 counterclockwise when viewed from FIGURE 4, to ts position illustrated in FIGURES 2 and 6, the lug 44 of the cam 39 engages the tongue 2.2 mounted in the door panel and acts t lock the door to the door frame.

The key plug 51 and its plate 53 are aligned in the position ndicated in solid lines in FIGURES 3 and 5, so that the legs 54 and 55 project vertically downwarclly and thereby allowng the flange 38 of the operators knob 36 to clear the legs or forks 54 and 55 so that the operators knob may be r0tated without interference, in locking the door.

Once the knob 36 has been rotated to its position as illustrated in FIGURES 2 and 6 to engage the tongue, the door is locked. The door may be unlocked by the key 52 from the outside, the casing member 24 being mounted on the outside face of the door. T he door will be unlocked by rotating the key and plug in a counterclockwise direction to ts position illustrated in dotted lines with the counterclockwise rotation causing the leg 54 to engage the face 65 of square body portion 38 of the operators knob, which engagement forces the operators knob to rotate clockwise, to return the lug 44 to ts vertical position and thereby unlock the door.

The body portion 38 is also provided with a vertical slot 67 acting as a night lock. The sliding knob 27 is adapted to =slide vertically upwardly to slide ts tongue member 35 into the slot 67 of the body portion 38 of the rotatable knob, and thus prevent the rotaton of the knob to thereby prevent the key plug and key from unlocking the door from the outside.

Thus, it will be seen that a novel door latch is provided which may be locked and unlocked from the inside and unlocked from the outside, and which has a night latch which prevents t from being unlocked from the outside.

It will be obvious that var-ious changes and departures may be made in the invention without departing from the spirit and scope thereof and, accordingly, it is not intended that the invention be limited te that specifically disclosed in the drawings or described in the specification, but only as set forth in the appended claims.

What is claimed is:

1. A night latch adapted to be mounted in a sliding door for locking the door to the door frame having a tongue engaging member therein, said night latch comprising a pair of elongated casing members adapted to be mounted on opposite sides of said door to be connected to one another, a rotatable operators knob, said rotatable knob having a lug portion disposed between said casing members and a finger operating portion projecting out of one of said casing members, said operators knob being adapted t0 rotate to swing a lug member into and out of engagement with said tongue member in said door frame, a key plug mounted ab0ve said operators knob and communicatng with the outer face of said other casing member, a key adapted to be inserted in said key plug, said plug having a downwardly depending leg adapted to engage said rotatable knob when said knob is rotated to move said lug into said locked position, with said leg engagement acting to rotate said lug out of engagement and thereby unlock the door, a sliding knob mounted beneath said rotary knob, said sliding knob having an upwardly projecting tongue, said rotatable knob having a recess in its body portion adapted to be in alignment with said tongue when said rotatable knob is in its locked position, said sliding knob being vertically slidable to slide said lug into said recess in said rotatable knob to prevent said rotatable knob from being rotated out of its locked position.

2. A night latch adapted to be mounted in a sliding door for locking the door to a door frame having a tongue engaging member thereon, said nght latch comprising a pair of elongated casing members adapted to be mounted on opposite sides of said do0r, said casing members each having a recessed channel along their lower portion, a rotatable eperators knob, said rotatable knob haveing a laterally projecting lug portion between said casing members, and a flange portion projecting out of one of said casing members to facilitate the manual rotation of said knob, said operators knob being adapted to rotate said lug member into and out of engagement with said tongue member in said door frame, 2. key plug rotatably mounted above said operators knob and adapted to receive a key through the other of said casing members and to be rotated by said key, said plug having a laterally extending leg portion, said operators knob having an elongated block portion fixed thereto, said plug being adapted to be rotated by said key to engage said block portion when said operators knob is in a locked position with said engagement of said block portion causing said operators knob t0 rotate said lug to an unlocked position, said block portion having a recessed slot, a sliding knob mounted beneath said operat0rs knob having a tongue to slidably engage said recessed slot to prevent said operators knob from rotatng out of a locked position.

References Cited by the Examiner UNITED STATES PATENTS 2,873,990 2/59 Friedman et al 292207 2983,000 5/61 Metzger. 3025693 3/62 Braginetz -100 ALBERT H. KAMPE, Primary Examner. 

1. A NIGHT LATCH ADAPTED TO BE MOUNTED IN A SLIDING DOOR FOR LOCKING THE DOOR TO THE DOOR FRAME HAVING A TONGUE ENGAGING MEMBER THEREIN, SAID NIGHT LATCH COMPRISING A PAIR OF ELONGATED CASING MEMBERS ADAPTED TO BE MOUNTED ON OPPOSITE SIDES OF SAID DOOR TO BE CONNECTED TO ONE ANOTHER, A ROTATABLE OPERATOR''S KNOB, SAID ROTATABLE KNOB HAVING A LUG PORTION DISPOSED BETWEEN SAID CASING MEMBERS AND A FINGER OPERATING PORTION PROJECTING OUT OF ONE OF SAID CASING MEMBERS, SAID OPERATOR''S KNOB BEING ADAPTED TO ROTATE TO SWING A LUG MEMBER INTO AND OUT OF ENGAGEMENT WITH SAID TONGUE MEMBER IN SAID DOOR FRAME, A KEY PLUG MOUNTED ABOVE SAID OPERATOR''S KNOB AND COMMUNICATING WITH THE OUTER FACE OF SAID OTHER CASING MEMBER, A KEY ADAPTED TO BE INSERTED IN SAID KEY PLUG, SAID PLUG HAVING A DOWNWARDLY DEPENDING LEG ADAPTED TO ENGAGE SAID ROTATABLE KNOB WHEN SAID KNOB IS ROTATED TO MOVE SAID LUG INTO SAID LOCKED POSITION, WITH SAID LEG ENGAGEMENT ACTING TO ROTATE SAID LUG OUT OF ENGAGEMENT AND THEREBY UNLOCK THE DOOR, A SLIDING KNOB MOUNTED BENEATH SAID ROTARY KNOB, SAID SLIDING KNOB HAVING AN UPWARDLY PROJECTING TONGUE, SAID ROTATABLE KNOB HAVING A RECESS IN ITS BODY PORTION ADAPTED TO BE IN ALIGNMENT WITH SAID TONGUE WHEN SAID ROTATABLE KNOB IS IN ITS LOCKED POSITION, SAID SLIDING KNOB BEING VERTICALLY SLIDABLE TO SLIDE SAID LUG INTO SAID RECESS IN SAID ROTATABLE KNOB TO PREVENT SAID ROTATABLE KNOB FROM BEING ROTATED OUT OF ITS LOCKED POSITION. 